#include <iostream>

using namespace std;

class Line
{
public:
    void setLength(double len);
    double getLength(void);
    Line();  // 这是构造函数
    ~Line(); // 这是析构函数声明

private:
    double length;
};

// 成员函数定义，包括构造函数
Line::Line(void)
{
    cout << "Object is being created" << endl;
}
Line::~Line(void)
{
    cout << "Object is being deleted" << endl;
}
void Line::setLength(double len)
{
    length = len;
}

double Line::getLength(void)
{
    return length;
}
// 程序的主函数
int main()
{
    Line line;

    // 设置长度
    line.setLength(6.0);
    cout << "Length of line : " << line.getLength() << endl;

    return 0;
}